Optical lens mounting clamp



Filed Jan. 19, 1939 ZNVENTOR. GEORGE A. SQUIER Patented Mar. 4, 1941 UNITED STATES rs cries v 1 Claim.

The present invention relates to an improvement in the mounting of an optical lens of'the rimless type. Such lenses are attached to a nose piece or bridge, or ear piece, by means of a mounting clamp. This mounting clamp customarily consists essentially of surface straps extending over each side of the lens, and an edge strap extending a short distance along the edge of the lens. A hole is drilled through the glass of the lens and some sort of fastening means, usually a screw, is passed through the surface straps and the hole to hold the mounting clamp in place on the lens.

It is the general object and nature of my present invention to provide a lens mounting clamp of the type indicated wherein the clamp is so constructed thatit is'expansible and contractible in width in order to accommodate varying thicknesses of lens without disturbing the alignment between the hole in the glass and the holes in the surface straps of the clamp and without the necessity of either filing the holein the glass or filing the glass under the surface straps to less thickness. My invention also provides a novel means of construction for fastening the surface straps of the clamp to the lens whereby a firm and secure attachment, not likely to become loosened in usage, or set up strain in the glass, is obtained; and in the assembly of which the operations are greatly simplified and. facilitated. Additional objects and advantages of my invention shall become apparent as the following description proceeds.

To the accomplishment of the foregoing and related ends, said invention, then, consists of the means hereinafter fully described and particularly pointed out in the claim.

The annexed drawing and the following description set forth in detail certain structure embodying the invention, such disclosed means constituting, however, but one of various structural forms in which the principle of the invention may be used.

In said annexed drawing:

Fig. l is a perspective View of the blank of metal used to form the mounting clamp of my invention; Fig. 2 is another perspective view of the blank after the formation of holes and apertures therein; Fig. 3 is an enlarged perspective view of my lens mounting clamp assembled on a relatively thin optical lens; Fig. 4 is a similar perspective View showing the mounting clamp assembled on a relatively thick optical lens; Fig. 5 is a plan view of the mounting clamp assembled on a lens; Fig. 6 is an enlarged sectional view taken substantially along. line 6-6 of Fig. 5; Fig. 7 is a perspectiveviewof the clamp mounting dowel pin; Fig. 8 is an enlarged sectional view illustrating a modified form of construction of the mounting clamp attachment to the lens; 5 Fig. 9 is an enlarged sectional view showing still another modified form of construction of the attachment of the mounting clamp to the lens; and. Fig. 10 is a fragmentary plan view looking at the bottom end of the mounting pin in Fig. 9. 10

Now referring more particularly to the drawing, the blank of metal stock of Fig. 1 consists of a central lens edge strap portion I with the lens surface strap portions 2 and 3 extending lateral therefrom. The blank of Fig. 1 is next operated upon to remove the metal from the portion I producing the kidney shaped aperture 4 and resulting in the formation of the oppositely disposed loops 5 and 6. A projecting portion 7 extends into the intermediate part of the aperture 4, and a slightly removed or concave portion 8 is located. opposite the projecting portion 1. Holes 9 and I B are located in the surface strap portions 2 and 3 respectively.

The loops 5 and 6 are deformable, i. e., expansible and contractible, in order to vary the resultant width of the edge strap portion of the clamp. The surface strap portions 2 and 3 are bent at right angles from the position as shown in Fig. 2, so that they overlie the lens. 30

In Fig. 3, the clamp is shown assembled upon a relatively thin lens A, wherein it will be noted that the loops 5 and 6 are contracted or relatively flattened out, as distinguished from the assembly in Fig. 4 on the relatively thick lens B where the loops 5 and 6 are expanded. The pro- 'ecting portion 7 serves as a base or joining point for the lug or end piece H of a bridge or ear piece. The removed portion 8, as will be seen in Fig. 3, forms a clearance space for the end of the projecting portion 1 when the clamp is mounted upon relatively thin lenses. The loops 5 and 6 constitute edge straps which overlie the full width of the lens and thus result in a much firmer and more efficient contact of the clamp with the lens, particularly in the edge portion, than has heretofore been employed.

Furthermore, the holes drilled in the lens for the reception of the mounting clamp fastening means are customarily located at a predetermined distance in from the edge of the lens. Heretofore, in fitting a mounting clamp to a lens, difficulty has been encountered due to the fact that where a clamp is attempted to be fitted upon a relatively thick lens, the holes in the surface straps fall at a. point nearer the edge of i the lens than the holes drilled through the lens;

and conversely, in the case of a thinner lens, the

holes in the surface straps are further away from the edge of the lens than the hole drilled in the latter, with the net result that certain expedients must be resorted to in order to compensate for such misalignment of the lens hole and the surface strap holes.

holes toward the edge, and bending the lens edge straps, with the incident disadvantage of producing an unsatisfactory and insecure fit of the mounting clamp on the lens. Further, such expedients previously employed have comprised the filing of the glass of the lens in the area between the hole and its edge to a lesser thickness, with the obvious disadvantageous result of seriously weakening the strength of the lens. My above described mounting clamp obviates these diffi 'culties and disadvantages, since the holes 9 and ID in my clamp are always at the same distance from the edge of the lens, and in alignment with mounting clamp to the lens is shown therein.

The holes in the surface straps '2 and 3 are countersunk as indicated at I2 and I3 respectively. A dowel pin as'shown in Fig. 7 is then inserted through the holes in the surface straps 2 and 3 and through the hole drilled in the lens C. The dowel. pin has a head portion 14 adapted to fit in the countersunk hole 13, a shank portion l5 adapted to snugly fit and align with the hole in the lens C, and a flattened, relatively thinner leg portion l6 which extends out through the other countersunk hole 12 in the surface strap 2. The leg portion I6 is first bent against the side of the countersunk hole l2, and then. around into a recess l'l formed in the surface strap 2. The excessive length of the leg I6 is of course cut off so that it will fit properly into the recess 11. The remaining space between the dowel, the hole in the lens C and in the countersunk hole [2 of the surface strap 2 is then filled with a relatively low melting point fluid metal, such as solder, indi-- cated at l8, which is allowed to solidify and then completes the fastening assembly.

Thus it will beseen that the dowel can be inserted from either side of the clamp, that it properly aligns the hole in the lens and the sur- In the modified form of construction shown in Fig 8, the fastening dowell is of a two-part construction, one part consisting of a stub dowel having a head 20 fitting in the countersunk hole 2| of the clamp surface strap, a short shank 22 of less diameter than that of the hole in the lens C, and an upset end portion 23 whose outer circumference has a clearance with respect to the hole in the lens C. The amount of this clearance is made sufiicient to permit the molten filling metal to flow past between the end portion 23 and the hole, during assembly of the parts. A similar stub dowel part 24 is inserted from the opposite surface strap, and the clearance space between the two dowel parts, the holes in the surface straps and the hole in the lens C is again filled with a fluid, subsequently solidified metal, as indicated at 25.

In the other modified form of construction shown in Fig. 9, the dowel is in the form of a split rivet having the head portion 30 fitting the countersunk hole in the top surface strap, the shank portion 3! of less diameter than that of the hole in the lens C and the two split legs 32 and 33. These legs 32 and 33 are bent outwardly over the lower surface strap, as indicated at 34 and 35 to fit into recesses in the raised ring 36 surrounding the edge of the hole in the lower surface strap. The clearance space is again filled with a filling metal, as indicated at 31.

Other modes of applying the principle of -my invention may beemployed instead of the one explained, change being made as. regards the structure herein disclosed, provided the means stated by any of the following claims or the equivalent of such stated means be employed.

I therefore particularly point out and distinctly claim as my invention! In a device of the character described, the combination of a lense having a hole therein, a mounting for the lens comprising lens surface straps engageable with the lens from opposite sides thereof and having openings in alignment with said hole, one of said straps being formed with a recess adjacent the opening therein, a fastening pin extending through said aligned openings and hole, said fastening pin having a head at one end thereof adapted to engage with the other of said straps, and a relatively thin, deformable body portion at the other end thereof adapted to be received in said recess to interlockably engage said fastening pin with said mounting, said thin body portion having at least a part thereof positioned within and partially filling the hole in said lens, and a filling metal cast into the space in said hole and in said openings unoccupied by said fastening pin for holding said fastening pin securely in place.

GEORGE A. SQUIER. 

